Organochlorine pesticide residues in Southern Ontario spring peepers

Spring peepers (Pseudacris crucifer) were analyzed by GC-ECD for 15 organochlorine pesticides of environmental significance. Only DDT, DDE, DDD, and dieldrin showed significant tissue accumulations in spring peepers. The area of collection had a history of extensive DDT application for mosquito control, but the practice of pesticide application was abandoned 26 years ago. Local extinctions of amphibians have been documented in the immediate area, and the long-term effects of organochlorine pesticide exposure are implicated as plausible causes of these extinctions.